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Multi-objective optimization of rolling schedule based on cost function for tandem cold mill 被引量:4
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作者 陈树宗 张欣 +3 位作者 彭良贵 张殿华 孙杰 刘印忠 《Journal of Central South University》 SCIE EI CAS 2014年第5期1733-1740,共8页
In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost fimction was proposed to determine the stand reductions, inter-stand tensions and r... In terms of tandem cold mill productivity and product quality, a multi-objective optimization model of rolling schedule based on cost fimction was proposed to determine the stand reductions, inter-stand tensions and rolling speeds for a specified product. The proposed schedule optimization model consists of several single cost fi.mctions, which take rolling force, motor power, inter-stand tension and stand reduction into consideration. The cost function, which can evaluate how far the rolling parameters are from the ideal values, was minimized using the Nelder-Mead simplex method. The proposed rolling schedule optimization method has been applied successfully to the 5-stand tandem cold mill in Tangsteel, and the results from a case study show that the proposed method is superior to those based on empirical formulae. 展开更多
关键词 tandem cold mill multi-object optimization rolling schedule cost function simplex algorithm
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Analysis of Cost Functions for Retrieving Sea Surface Salinity 被引量:4
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作者 QI Zhen WEI Enbo 《Journal of Ocean University of China》 SCIE CAS 2012年第2期147-152,共6页
Two kinds of Bayesian-based cost functions (i.e., the unconstrained cost function and parameter-constrained cost function) are investigated for retrieving the sea surface salinity (SSS). In low SSS regions, we have an... Two kinds of Bayesian-based cost functions (i.e., the unconstrained cost function and parameter-constrained cost function) are investigated for retrieving the sea surface salinity (SSS). In low SSS regions, we have analyzed the sensitivity of the two cost functions to geophysical parameters. The results show that the unconstrained cost function is valid for retrieving several parameters (including SSS, wind speed and significant wave height), and the constrained cost function, which largely depends on the accuracy of reference values, may lead to large retrieval biases. Furthermore, as a retrieval parameter, the sea surface temperature (SST) can re-sult in the divergence of other geophysical parameters in an unconstrained cost function due to the strong sensitivity of brightness temperature to SST. By using the unconstrained cost function and the simulated brightness temperature TB with white noises, the retrieval biases of SSS are discussed with the following two procedures. Procedure a): the simulated TB values are first averaged, and then SSS is retrieved. Procedure b): the SSS is directly retrieved from the simulated TB , and then the retrieved SSS values are aver-aged. The results indicate that, for low SSS and SST distributions, the SSS retrieval by procedure a) has less biases compared with that by procedure b), while the two procedures give almost the same retrieval results for high SSS and SST sea regions. 展开更多
关键词 cost function sea surface salinity and temperature brighmess temperature
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Competitive analysis of price online inventory problem with cost function 被引量:1
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作者 HAN Shu-guang GUO Jiu-ling +1 位作者 ZHANG Lu-ping HU Jue-liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第4期493-502,共10页
In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online alg... In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online algorithm based on cost function.The competitive ratio of the online algorithm is given for each variant,which is a performance measure of an online algorithm.More importantly,we show that the online algorithm is optimal. 展开更多
关键词 inventory problem price online cost function competitive analysis
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Handover improvement based on cost function and user fairness for cellular relay enhanced LTE networks
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作者 Chen Muqiong Ji Hong Li Xi 《High Technology Letters》 EI CAS 2011年第3期299-304,共6页
In order to optimize handover target selection and achieve better handover performance in cellular relay networks under the long term evolution (LTE) system, a novel handover measurement and decision scheme based on... In order to optimize handover target selection and achieve better handover performance in cellular relay networks under the long term evolution (LTE) system, a novel handover measurement and decision scheme based on cost function is proposed in the paper. The relay-enhanced network provides user equipment (UE) multiple handover choices from neighbor base stations or relays. This may result in different overhead, resource utility and traffic load which attaches importance to proper handover schemes. Compared with traditional handover measurement and decision schemes, the proposed scheme adopts reference signal receiving quality (RSRQ) in the measurement stage and uses a modified signal cost function considering signal overhead in different handover types and expected long-term throughput of UE. Besides, UE fairness and sector resource utilization are taken into account as well. Theory analysis and simulation results prove that the proposed scheme can enhance cell throughput, decrease handover delay and signal overhead, and improve UE fairness. 展开更多
关键词 HANDOVER RELAY cost function FAIRNESS
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Is a Single Product Cost Function Appropriate for Institutions of Higher Education? Empirical Evidence From China's Research Universities*
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《Economics World》 2016年第2期47-59,共13页
Many studies exist in the literature of scale and scope economies in institutions of higher education employing multi-product cost functions of quadratic, constant elasticity substitution (CES), or hybrid translog f... Many studies exist in the literature of scale and scope economies in institutions of higher education employing multi-product cost functions of quadratic, constant elasticity substitution (CES), or hybrid translog form. A single product cost function is normally considered inadequate and yield distorted results. Both quadratic and single product cost functions have been applied to university data from China's Ministry of Education (MOE). This study compares those two methods and their statistical results and finds that ray economies of scale from these two cost functions are quite similar though the single product cost function which can not be used to calculate product-specific economies of scale or economies of scope. 展开更多
关键词 single and multi-product cost function economies of scale economies of scope China's researchuniversities
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A Reliable and Secure Smart Grid Communication Network Using a Comprehensive Cost Function
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作者 Vahid Kouhdaragh 《Journal of Energy and Power Engineering》 2017年第2期115-126,共12页
SG (smart grids) is an intelligent power grid in which the diverse nodes should communicate different types of information which have different communication requirements with CS (control stations). There exist se... SG (smart grids) is an intelligent power grid in which the diverse nodes should communicate different types of information which have different communication requirements with CS (control stations). There exist several RATs (radio access technologies), with diversification in quality of service character which respect to the SG nodes communication requirements. On the other side, spectrum is becoming a rare source and its demands request is increasing exponentially. Therefore, resource allocation to support different types of SG nodes should be elaborated so that the resource efficiency is maximized while the SG communication requirements are respected. Using a CF (cost function) based on the SG node requirements and RATs characteristics to find the desirability value of every RATs for a certain node type accomplish this goal in combination with prioritizing the different SG nodes types based on SG goals by creating a priority table for RATs and different SG node types. The main node communication requirements are formulized to be used in the CF in this paper. The numerical results show that the proposed method defines the desirability value of each RAT for a certain SG node type that helps to make a priority table by using the SG node prioritization table. 展开更多
关键词 Smart grid node prioritization cost function communication requirements spectral efficiency heterogeneous network.
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Resource Allocation Using SPA Based on Different Cost Functions in Elastic Optical Networks
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作者 Mehdi Tarhani Sanjib Sarkar +1 位作者 Morad Khosravi Eghbal Mehdi Shadaram 《Journal of Computer and Communications》 2019年第10期14-20,共7页
Routing, modulation and spectrum allocation in elastic optical networks is a problem aiming at increasing the capacity of the network. Many algorithms such as shortest path algorithm can be used as the routing section... Routing, modulation and spectrum allocation in elastic optical networks is a problem aiming at increasing the capacity of the network. Many algorithms such as shortest path algorithm can be used as the routing section of this problem. The efficiency of these algorithms is partly based on how the cost of each link is defined. In this study, we considered several basic metrics in cost of network links and compared their effects on the network capacity. In particular, the static costs and the dynamic costs were evaluated and compared. For dynamic scenarios, compared to static scenarios, at least one additional factor, the usage of the links, was added. We further considered a new factor that is based on probability of accommodating the signal at a given time in any given link. The results show that, among them, the shortest path algorithm provides the least blocking probability when the cost is a combination of link length and the abovementioned possibility/usage of the link. 展开更多
关键词 ELASTIC Optical Networks ROUTING Modulation Spectrum ALLOCATION cost function Shortest Path Algorithm
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Cost Effective Operating Strategy for Unit Commitment and Economic Dispatch of Thermal Power Plants with Cubic Cost Functions Using TLBO Algorithm
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作者 E. B. Elanchezhian S. Subramanian S. Ganesan 《Journal of Power and Energy Engineering》 2015年第6期20-30,共11页
This paper deals with a Unit Commitment (UC) problem of a power plant aimed to find the optimal scheduling of the generating units involving cubic cost functions. The problem has non convex generator characteristics, ... This paper deals with a Unit Commitment (UC) problem of a power plant aimed to find the optimal scheduling of the generating units involving cubic cost functions. The problem has non convex generator characteristics, which makes it very hard to handle the corresponding mathematical models. However, Teaching Learning Based Optimization (TLBO) has reached a high efficiency, in terms of solution accuracy and computing time for such non convex problems. Hence, TLBO is applied for scheduling of generators with higher order cost characteristics, and turns out to be computationally solvable. In particular, we represent a model that takes into account the accurate higher order generator cost functions along with ramp limits, and turns to be more general and efficient than those available in the literature. The behavior of the model is analyzed through proposed technique on modified IEEE-24 bus system. 展开更多
关键词 CUBIC cost functionS RAMP Rate TEACHING Learning Based Optimization Unit COMMITMENT
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Natural Monopoly and Mixed Ownership Reform--Based on Natural Experiment and Cost Function Analysis Method
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作者 Chen Lin 《China Economist》 2018年第5期60-83,共24页
Despite a multitude of theoretical discussions on China's mixed ownership reform, very few studies have addressed realistic questions concerning the implementation of the reform. The Resolutions of the Third Plenu... Despite a multitude of theoretical discussions on China's mixed ownership reform, very few studies have addressed realistic questions concerning the implementation of the reform. The Resolutions of the Third Plenum of the 18 th CPC Central Committee and other reform strategies have outlined the reform of sectors with natural monopoly, including urban public utility sectors. The question is how mixed ownership reform should be carried out in sectors of natural monopoly, or which public utilities sectors should enjoy priority of mixed ownership reform. To answer this question, this paper employs data of large public utility enterprises in China from 1998 to 2008, and estimates the natural monopoly attribute at the industry level and corporate total factor productivity(TFP) using cost function analysis method excluding the impact of product price factor. Based on the difference-indifferences-in-differences(DDD) method of natural experiment, an empirical test is carried out for the relationship among natural monopoly, mixed ownership reform and corporate productivity. Our results suggest that:(1) Statistically, mixed ownership reform cannot significantly increase corporate TFP in sectors with natural monopoly;(2) mixed ownership reform should not be carried out indiscriminately on a nationwide basis and for all public utilities sectors. Such an attempt of reform without distinguishing natural monopoly and the level of competitiveness is fraught with policy uncertainties;(3) relative to sectors with natural monopoly, corporate productivity in competitive sectors after mixed ownership reform will improve more significantly and enjoy greater "policy dividends" of institutional reform. Therefore, mixed ownership reform should be carried out first in competitive sectors. 展开更多
关键词 mixed OWNERSHIP REFORM NATURAL MONOPOLY cost function NATURAL experiment difference-in-differences-in-differences(DDD)method
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Composite Cost Function Based Solution to the Unit Commitment Problem
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作者 Srikrishna Subramanian Radhakrishnan Anandhakumar 《Smart Grid and Renewable Energy》 2010年第2期88-97,共10页
This paper presents a new approach via composite cost function to solve the unit commitment problem. The unit com-mitment problem involves determining the start-up and shut-down schedules for generating units to meet ... This paper presents a new approach via composite cost function to solve the unit commitment problem. The unit com-mitment problem involves determining the start-up and shut-down schedules for generating units to meet the fore-casted demand at the minimum cost. The commitment schedule must satisfy the other constraints such as the generating limits, spinning reserve, minimum up and down time, ramp level and individual units. The proposed algorithm gives the committed units and economic load dispatch for each specific hour of operation. Numerical simulations were carried out using three cases: four-generator, seven-generator, and ten-generator thermal unit power systems over a 24 h period. The produced schedule was compared with several other methods, such as Dynamic programming, Branch and bound, Ant colony system, and traditional Tabu search. The result demonstrated the accuracy of the proposed method. 展开更多
关键词 COMPOSITE cost function Generation SCHEDULING Unit COMMITMENT
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Pancreatic function,quality of life and costs at long-term follow-up after acute pancreatitis 被引量:15
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作者 Bodil Andersson Marie-Louise Pendse Roland Andersson 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第39期4944-4951,共8页
AIM:To evaluate long-term endocrine and exocrine pancreatic function,quality of life and health care costs after mild acute pancreatitis and severe acute pancreatitis(SAP).METHODS:Patients prospectively included in 20... AIM:To evaluate long-term endocrine and exocrine pancreatic function,quality of life and health care costs after mild acute pancreatitis and severe acute pancreatitis(SAP).METHODS:Patients prospectively included in 2001-2005 were followed-up after 42(36-53)mo.Pancreatic function was evaluated with laboratory tests,the oral glucose tolerance test(OGTT),fecal elastase-1 and a questionnaire.Short Form(SF)-36,was completed.RESULTS:Fourteen patients with a history of SAP and 26 with mild acute pancreatitis were included.Plasma glucose after OGTT was higher after SAP(9.2 mmol/L vs 7.0 mmol/L,P=0.044).Diabetes mellitus or impaired glucose tolerance in fasting plasma glucose and/or 120 min plasma glucose were more common in SAP patients(11/14 vs 11/25,P=0.037).Sick leave,time until the patients could take up recreational activities and time until they had recovered were all longer after SAP(P <0.001).No significant differences in SF-36 were seen between the groups,or when comparing with age and gender matched reference groups.Total hospital costs,including primary care,follow-up and treatment of complications,were higher after SAP(median€16572 vs €5000,P<0.001).CONCLUSION:Endocrine pancreatic function was affected,especially after severe disease.SAP requires greater resource use with long recovery,but most patients regained a good quality of life. 展开更多
关键词 Acute PANCREATITIS ENDOCRINE function EXOCRINE function Quality of life cost
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面向多机异步测向系统的多目标数据关联算法
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作者 周晓 孙子豪 +2 位作者 苏盈 王丽 牟新刚 《系统工程与电子技术》 北大核心 2026年第2期392-401,共10页
针对多载机协同光电探测系统执行多目标搜索任务时的测向数据关联问题,提出一种基于异步测向定位模型的数据关联算法。首先分析出传统关联代价模型的代价函数受测向数据异步采集的影响较大,再利用传感器误差等先验参数构建基本约束对关... 针对多载机协同光电探测系统执行多目标搜索任务时的测向数据关联问题,提出一种基于异步测向定位模型的数据关联算法。首先分析出传统关联代价模型的代价函数受测向数据异步采集的影响较大,再利用传感器误差等先验参数构建基本约束对关联组合进行初步筛选,然后再通过光电探测系统的搜索原理构建异步测向关联模型进行代价关联。仿真实验结果表明,相比于其他关联模型,所提算法模型关联正确率维持在90%以上,受载机和目标数量影响更小,算法耗时相对较低,性能更高。 展开更多
关键词 测向定位模型 多目标 关联代价函数 数据关联算法
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Optimal investment with transaction costs based on exponential utility function:a parabolic double obstacle problem
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作者 BAO Qun-fang YANG Jing-yang +1 位作者 SUN Chao LI Sheng-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第4期483-492,共10页
This paper concerns optimal investment problem with proportional transaction costs and finite time horizon based on exponential utility function. Using a partial differential equation approach, we reveal that the prob... This paper concerns optimal investment problem with proportional transaction costs and finite time horizon based on exponential utility function. Using a partial differential equation approach, we reveal that the problem is equivalent to a parabolic double obstacle problem involving two free boundaries that correspond to the optimal buying and selling policies. Numerical examples are obtained by the binomial method. 展开更多
关键词 Optimal investment transaction costs double obstacle problem stochastic control exponential utility function.
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NISQ量子线路高频-密集量子门集策略优化算法
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作者 李晖 刘述娟 +2 位作者 鞠明媚 王杰鹏 姬迎松 《计算机科学》 北大核心 2026年第4期112-120,共9页
在噪声中等规模量子(Noisy Intermediate-Scale Quantum,NISQ)时代,考虑硬件耦合约束限制,并非所有量子门均可直接执行,通常需要利用额外引入的SWAP操作实现量子比特交换后,逻辑线路才能直接运行于物理硬件上。为了避免传统量子线路映... 在噪声中等规模量子(Noisy Intermediate-Scale Quantum,NISQ)时代,考虑硬件耦合约束限制,并非所有量子门均可直接执行,通常需要利用额外引入的SWAP操作实现量子比特交换后,逻辑线路才能直接运行于物理硬件上。为了避免传统量子线路映射过程中SWAP操作带来的额外开销,对量子比特频度进行定义,提出一种高频-密集量子门集策略(High Frequency-Dense Quantum Gate Set Strategy,HF-DQGS),并将其应用于量子线路映射。基于量子比特频度,对CNOT门进行优先级划分,定义高频-密集量子门集;利用多变量成本函数对候选SWAP门的实际开销进行评估,确定待执行的SWAP操作;根据基于量子比特频度的最优SWAP门评价准则,SWAP操作后对评价函数进行比较,筛选出最优的SWAP门。实验结果表明,HF-DQGS能够显著减少附加SWAP门的数量,并在一定程度上减少CNOT门的数量。具体而言,在t|ket〉和Qiskit编译器上的测试结果显示,额外SWAP门的数量平均分别减少了36.6%和47.8%,CNOT门的数量平均分别减少了13%和13.4%。 展开更多
关键词 量子计算 量子线路映射 高频-密集量子门集策略 多变量成本函数 最优SWAP门评价准则
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TLS Blind Recognition Algorithm of LDPC Codes
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作者 Ning Xiaoyan Sun Jingjing +1 位作者 Wang Zhenduo Sun Zhiguo 《China Communications》 2026年第2期112-121,共10页
Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively ... Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively high row weights,the existing blind recognition algorithms based on a candidate set generally perform worse.In this paper,we propose a blind recognition method for LDPC codes,called as tangent function assisted least square(TLS)method,which improves recognition performances by constructing a new cost function.To characterize the constraint degree among received vectors and paritycheck vectors,a feature function based on tangent function is constructed in the proposed algorithm.A cost function based on least square method is also established according to the feature function values satisfying the parity-check relationship.Moreover,the minimum average value in TLS is obtained on the candidate set.Numerical analysis and simulation results show that recognition performances of TLS algorithm are consistent with theoretical results.Compared with existing algorithms,the proposed method possesses better recognition performances. 展开更多
关键词 blind recognition cost function least square low-density parity-check(LDPC)codes
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基于MLE自适应UKF算法在Levy噪声下速度估计研究
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作者 张睿涵 杨光永 +2 位作者 吴立煌 高钏棋 徐天奇 《仪表技术与传感器》 北大核心 2026年第2期121-126,共6页
针对多普勒测速仪在水下作业易受Levy噪声干扰,导致速度估计精度显著下降的问题,提出一种基于极大似然估计(maximum likelihood estimation,MLE)的自适应无迹卡尔曼滤波(unscented Kalman filter,UKF)方法。该方法在UKF的基础上结合滑... 针对多普勒测速仪在水下作业易受Levy噪声干扰,导致速度估计精度显著下降的问题,提出一种基于极大似然估计(maximum likelihood estimation,MLE)的自适应无迹卡尔曼滤波(unscented Kalman filter,UKF)方法。该方法在UKF的基础上结合滑动窗口机制,以实现局部经验MLE对噪声协方差的在线估计;并利用Huber代价函数对残差进行非线性加权,增强系统对异常值的鲁棒性。仿真结果表明:在Levy噪声环境下,所提方法相比于UKF算法,X与Y方向速度估计误差分别降低65.3%和64.7%,显著提升了估计精度和抗干扰能力。 展开更多
关键词 多普勒测速仪 Levy噪声 极大似然估计 滑动窗口机制 无迹卡尔曼滤波 速度估计 Huber代价函数
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融合骨架约束域的RRT-Connect路径规划算法
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作者 聂铭杰 向贤宝 +3 位作者 蔡芸 蒋林 汤勃 潘艳桥 《重庆理工大学学报(自然科学)》 北大核心 2026年第1期123-131,共9页
针对RRT-Connect路径规划算法存在采样随机性强、路径点冗余及搜索效率低等问题,提出了一种融合骨架约束域的RRT-Connect路径规划算法。首先,对栅格地图进行预处理,提取骨架并生成全局骨架地图,基于给定的起始点和目标点在骨架上搜索初... 针对RRT-Connect路径规划算法存在采样随机性强、路径点冗余及搜索效率低等问题,提出了一种融合骨架约束域的RRT-Connect路径规划算法。首先,对栅格地图进行预处理,提取骨架并生成全局骨架地图,基于给定的起始点和目标点在骨架上搜索初始路径,并扩展该路径生成的骨架约束区域;其次,为降低RRT-Connect算法的采样随机性,将采样点限制在生成的骨架约束域内,并引入目标节点偏置策略;然后,为减少路径冗余点,引入启发式代价函数,选取代价值最低的节点作为扩展节点;最后,通过路径裁剪结合二次贝塞尔曲线进行路径平滑优化,通过构建不同复杂度的仿真场景和实际环境进行对比实验。实验结果表明,所提算法可以高效地生成一条无碰撞且包含初始节点与目标节点的最优路径,提升路径生成效率。 展开更多
关键词 RRT-Connect算法 骨架约束域 目标偏置 启发式代价函数 路径裁剪
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自适应脊线提取在轴箱轴承故障诊断中的应用
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作者 王星童 何霞 +1 位作者 丁建明 席亚军 《振动.测试与诊断》 北大核心 2026年第1期115-122,219,220,共10页
针对时变转速下现有代价函数在脊线提取中存在局限性、搜索区域选择对脊线提取误差较大的问题,基于动态路径规划原理与时频分析技术,提出了一种基于自适应代价函数及变带宽可迭代脊线提取方法。首先,根据信号在时频图上的亮度梯度,将脊... 针对时变转速下现有代价函数在脊线提取中存在局限性、搜索区域选择对脊线提取误差较大的问题,基于动态路径规划原理与时频分析技术,提出了一种基于自适应代价函数及变带宽可迭代脊线提取方法。首先,根据信号在时频图上的亮度梯度,将脊线搜索区域自适应限制在窄带内,缩小提取范围并降低干扰影响;其次,构造融合峰值点幅值缩放与频率跳变惩罚因子的可调节代价函数,结合动态路径规划求解候选脊点的累计代价并完成最优路径回溯,实现单条脊线的精准提取;然后,采用在同一时频图内多次迭代的方式提取瞬时轴转频率、瞬时故障特征频率及其谐波等多条脊线;最后,利用提取脊线之间的平均比值与故障特征阶次进行匹配,从而实现故障诊断。研究结果表明:与现有流行方法比较,该方法在脊线提取准确度和抗噪上均有较高的性能,对于内圈故障和外圈故障脊线提取结果的平均误差分别为0.42%和0.2%,有效解决了时变转速下轴承故障脊线提取的精度与抗噪难题,为车辆轴箱轴承在复杂工况下的健康监测提供了高效、可靠的技术方案。 展开更多
关键词 轴承故障诊断 动态路径规划 代价函数 脊线提取 时变转速
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基于HDR融合和SR融合相结合的图像增强方法
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作者 徐雪峰 黄余 《兵工自动化》 北大核心 2026年第1期79-83,108,共6页
针对图像增强问题,提出一种将高动态范围融合与超分辨率融合相结合的系统方法。对摄相机进行校准,以模拟摄相机的光度特性,获得估计摄相机的响应曲线;执行自动图像采集过程,在不同的视角和不同的摄相机参数(如不同的曝光时间)下拍摄,作... 针对图像增强问题,提出一种将高动态范围融合与超分辨率融合相结合的系统方法。对摄相机进行校准,以模拟摄相机的光度特性,获得估计摄相机的响应曲线;执行自动图像采集过程,在不同的视角和不同的摄相机参数(如不同的曝光时间)下拍摄,作为捕捉具有适当图像融合所需变化的多个输入图像;对于色调映射,采用梯度域融合方法进行,将亮度图压缩到强度域,在最终图像中尽可能多地保持细节,同时仍然保持逼真的外观;对于图像融合步骤,进行光度和几何配准,建立输入图像中像素之间的对应关系。以提高分辨率和最大化动态范围为目标进行图像融合,从而获得最终增强的图像。采用不同类型摄像机拍摄的图像实例,结果表明该系统方法具有可行性。 展开更多
关键词 图像增强技术 高动态范围 超分辨率 摄相机响应曲线 图像融合 辐照度 成本函数
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基于系统保护理念的国土空间功能分区与管控策略
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作者 张晓琳 金晓斌 +3 位作者 周寅康 刘洋洋 王伟峰 胡尔查 《农业工程学报》 北大核心 2026年第2期287-297,共11页
国土空间功能分区是构建可持续开发保护格局、提升资源利用效率的重要途径,但传统方法多侧重功能相似性识别,缺乏对生态、农业、城镇等多类管理目标及成本效益的系统统筹。该研究引入系统保护理念,构建“目标-成本-效益”协同优化的国... 国土空间功能分区是构建可持续开发保护格局、提升资源利用效率的重要途径,但传统方法多侧重功能相似性识别,缺乏对生态、农业、城镇等多类管理目标及成本效益的系统统筹。该研究引入系统保护理念,构建“目标-成本-效益”协同优化的国土空间功能分区理论框架,综合运用适宜性评价、景观格局指数分析和分区优化模型(Marxan with Zones),形成由主导功能区与功能混合区构成的分区方法,并在江阴市开展实证研究。结果表明:1)优化分区方案显著提升了自然生态系统的代表性与保护效益,乔木林地、灌木林地等关键生态系统的保护比例提升至30%以上。2)在满足生态保护目标的前提下,农业与城镇功能空间得到适度拓展,基本农田和城镇开发规模较现状有所增加,单位面积成本增幅保持在10%以内,体现出较强的综合效益。3)优化方案在空间结构上呈现较高的集聚性与协调性,集约化农区聚集度由71.21提升至88.5,通过功能混合区在严格保护区与城镇建设区之间构建了有效的过渡带,缓解了潜在的空间利用冲突。研究可为高冲突区域优化国土空间格局和完善主体功能区制度提供方法与实践参考。 展开更多
关键词 国土空间功能分区 系统保护理念 成本效益 Marxan模型 江阴市
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